Member Churches

CRC - Christian Reformed Churches in the Netherlands (CGK - Christelijke Gereformeerde Kerken in Nederland)
EPCEW - Evangelical Presbyterian Church in England and Wales (including Sweden)
EPCI - Evangelical Presbyterian Church in Ireland
FCS - Free Church of Scotland
FCC - Free Church of Scotland (Continuing)
RCN - Reformed Churches in the Netherlands (GKV - Gereformeerde Kerken vrijgemaakt in Nederland)
RPCI - Reformed Presbyterian Church of Ireland
RCS - Reformed Churches of Spain (IRE - Iglesias Reformadas de España)

Observers

MTW - Mission to the World
ERKWB - Evangelisch Reformierte Kirche Westminster Bekentuisses
KKERPE - Reformed Presbyterian Church of Central & Eastern Europe
REC - Romania Evangelical Church